His Apartment Harem: The Performance (His Asian Apartment Harem #4)
O. L. Tyme

Exhausted from work, Mark wants nothing more than a quiet evening by himself to rest. So of course he is immediately interrupted by a hammering on his apartment door.
As he reluctantly opens up, he finds Seo-yun looking for a she needs to borrow his guitar for an open-mic night.
He agrees on one he goes with her to make sure his guitar is ok.
Reluctantly agreeing, the two of them head off a musty old rock bar. But when Seo-yun has a bout of stage fright, Mark needs to find a way to relax her by giving the performance of a lifetime.